Acid Base Balance Flashcards
what is normal pH
7.35-7.45
is arterial or venous blood more acidic
venous
what is normal bicarbonate
23-27
what is normal PCO2
35-45
what is the pulmonary component
pCO2 partial pressure
what is the metabolic component
bicarbonate
what is the action of carbonic anhydrase
converts CO2 + H2O -> carbonic acid
and
converts carbonic acid > H+ + HCO3-
how is bicarbonate controlled by the kidneys
generating new HCO3- and increasing/decreasing reabsorption
what are the kidneys dependent on to be able to control bicarbonate
H+ secretion
is new HCO3- formed is acidosis or alkalosis
acidosis
what basic buffer of the filtrate does H+ combine with for HCO3- formation
phosphate (then excreted)
what is the 2nd buffer in severe acidosis when phosphate is used up
ammonia
“resorting pH, irrespective of HCO3- and CO2” describes what
compensation
” resorting pH, HCO3- and pCO2” describe what
correction
what are the blood buffers
haemoglobin and bicarbonate
disadvantage of the blood buffer system
depleted quickly
advantage of the blood buffer system compared to the renal buffer system
immediate (renal takes hours - days)
pH <7.35, PCO2 >45
uncompensated respiratory acidosis
basic pathology of respiratory acidosis
CO2 retention
how do the kidneys buffer respiratory acidosis
increase H+ secretion, all HCO3- reabsorbed
pH >7.45, CO2 <35
uncompensated respiratory alkalosis
basic pathology of respiratory alkalosis
excess co2 removal
what effect does respiratory acidosis have on the equilibrium
moves equilibrium right
what effect does respiratory alkalosis have on the equilibrium
moves equilibrium left
